Appartement tout confort, vue Tage et château, garage optionnel/Wi-Fi, A/C

I regret that the guest only informed me by email at check-out that there was a problem with the air conditioning in one of the bedrooms and not before. I always test all air conditioning units before guests check in, making sure to switch to Celsius or Fahrenheit depending on the guest's nationality, and they all worked. After the guest checked out, I tried the air conditioning in the bedroom that supposedly wasn't working and didn't detect any problems. I honestly don't know what happened, but no other guest has complained to date. Regarding the locks, I think the guest referring to the building's entrance lock. Sometimes you have to turn the key a few times to open it, but I usually warn guests and show them how to open the door. The building's lock is the condominium's responsibility, and I've already informed management. This is the ansewr